Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Nomeie o tipo para as atividades principais da sede.
 ###Tabelas: CREATE TABLE medals_table (medals_table_id AUTO_INCREMENT PRIMARY KEY, Rank INT, Nation VARCHAR, Gold INT, Silver INT, Bronze INT, Total INT) CREATE TABLE seasonal_ratings_broadcast_history (seasonal_ratings_broadcast_history_id AUTO_INCREMENT PRIMARY KEY, Season INT, Network VARCHAR, Time slot VARCHAR, Season premiere VARCHAR, Season finale VARCHAR, Episode count INT, TV season VARCHAR, Season rank VARCHAR, Viewers (in millions) INT) CREATE TABLE north_korea_dprk (north_korea_dprk_id AUTO_INCREMENT PRIMARY KEY, City VARCHAR, Korean VARCHAR, Hancha VARCHAR, Province VARCHAR, Population (2008) INT) CREATE TABLE four-abreast_cabin (four-abreast_cabin_id AUTO_INCREMENT PRIMARY KEY, Model VARCHAR, Seats VARCHAR, Period VARCHAR, Built INT, Country VARCHAR) CREATE TABLE subsidiaries_and_associates (subsidiaries_and_associates_id AUTO_INCREMENT PRIMARY KEY, Company VARCHAR, Type VARCHAR, Principal activities VARCHAR, Incorporated in VARCHAR, Group's Equity Shareholding (10 March 2010) VARCHAR)  
SELECT Type FROM subsidiaries_and_associates WHERE Principal activities = headquarters